1880.] NATURAL SCIENCES OP PHILADELPHIA. 317 



flower matured, and the anthers were ready to fall, thej' were exam- 

 ined the four short ones were empty sacs the three lower ones 

 proved they had not served any purpose to the bees, for they 

 were full of pollen. There could be no doubt that, perfect and 

 full of pollen as thoj^ were, they served no purpose that I could 

 see either to the flower or to its insect visitors. Hive bees on 

 honey-collecting expeditions hunted around among the base ot 

 the petals, but were not, apparently, well rewarded for their work. 

 No pollen could be detected on the stigmatic surface; but as about 

 three out of every twelve flowers yielded a pod, they were evi- 

 dently fertilized in some way. On the 30th of July I covered 

 one panicle that had not yet opened a blossom, with a gauze bag 

 twelve inches wide and eighteen inches deep, tied at the bottom 

 to prevent ingress. Not one of these enclosed flowers produced 

 a seed vessel, nor could I see that any one anther " opened at the 

 apex." The membrane covered it as completely as it did in the 

 unopened flower. 



Now all these observations confirm those of Mr. Todd in the 

 other plants except in the following particulars : As in my 

 case, he found that the bees never attempted to collect pollen 

 from the longer and lower anthers, but " b}'' the movement of 

 her feet the larger stamen is repeatedly sprung backward, and 

 as often throws a cloud of pollen on one side of her body." I 

 am sure no pollen was ejected in this way from Cassia Marilan- 

 dica, for the membrane at the apex was not even ruptured when 

 the stamens were ready to fall. In regard to the manner in which 

 the pollen is extracted, he found that " this she does by seizing 

 each anther near its base between her mandibles, and, with a sort 

 of milking motion, crowds the pollen out of the terminal pore." 

 If this were the general way there would be no necessity for any 

 pollen being ejected from the long stamens, for the stigma would 

 certainly receive some during the " milking " process ; and the 

 pore at the apex in the long anther is beyond the line of the 

 stigma, so that on ejection from the pore the pollen would go 

 still further beyond. At any rate I am satisfied that in this 

 species the anther cases did not under my observation ultimately 

 split longitudinally, as stated by Dr. Torrey in an allied species, 

 nor was there any drawing out of the pollen, as observed by Prof. 

 Todd. It is abstracted solely through the pores; and although I 

 could see no evidence that such was actually the case, I suspect 



